Recording apparatus



F Dec. .0, 1944. o. WlTTEL RECORDING APPARATUS Flled March 51 1943 DTTEI WI TTEL INVENTOR BY W M ATTORNEY? decided disadvantages arise.

Patented Dec. 5, 1944 RECORDING APPARATUS Otto Wittel, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Application March 31, 1943, Serial No. 481,311

6 Claims.

The present invention relates to recording apparatus for making a visible record of the changes of a variable condition, such as temperature, pressure, etc., over a period of time, and

particularly to the manner of mounting the re-.-

cording stylus or pencil in such a manner that a sharp point is automatically maintained there- Apparatus for makingvisible recordings continuously, or intermittently, of changes in a variable condition, such as temperature, pressure, etc., on a suitable chart or other recording surface, are well known to the art. Generally, these apparatus include a movable recording surface and a recording stylus normally held in engagement therewith for making a trace thereon. The stylus is generally moved laterally of the direction of movement of the recording surface in response to variations in the condition which it is desired to measure and record. Although a pen is desirable and satisfactory as a stylus in many instances, there are many instances in which it is necessary or desirable to use a pencil or a plain pointed stylus instead of a pen.

Instances where a recording pen is not desirable may include recorders which are designed to make long, continuous traces.which would require a pen having an ink capacity which is impractical; recorders where there is a rapid, relative movement between the recording surface and the pen so that the pen would have to be capable of a rapid feed, as well as a fine trace; or intermittent operation, in which case the ink in a pen would tend to dry and the pen would fail to start flowing at the instant desired.

The recording stylus may be a pencil, or a plain pointed member adapted to make a trace on a special wax surface recording paper. In any event, in order to obtain a fine, sharp and even trace the pencil or stylus should be maintained pointed and should not be allowed to become flattened on one side due to continuous wear. If the pencil or stylus is allowed to become blunt or flattened on one side during use, at least two First, the width of the trace varies during a recording and this is confusing, especially if the recording surface has rather closely spaced markings which the trace s to be referred to. Secondly, the stylus or pencil is usually spring held in contact with the record ng surface, and'a blunt stylus requires con-' siderably more pressure to make a distinct trace than a pointed one. Therefore, if the apparatus s started with a pointed stylus and the pressure is adjusted to give a good trace with a pointed stylus or pencil, as the stylus starts to wear flat on one side the pressure thereon must be gradually increased if a distinct visible trace is to be maintained.

one object of the present invention is to provide a recording apparatus of the type described including means for automatically keeping th stylus or pencil pointed.

Another object is to provide an apparatus of the type set forth including a rotatable stylus and means for automatically rotating the same relative to the recording surface durin a recording operation in order to maintain the stylus pointed. 7

And another object is to provide a recording apparatus of the type set forth in which the movement of the stylus relative to the recording surface is utilized to cause the oscillation of the stylus relative to its support to maintain the same pointed.

And yet another object is to provide a stylus oscillating means which includes a pulley surrounding and fixed to the stylus and normally in engagement with a substantially stationary belt extending in a direction substantially laterally of the direction of movement of the recording surface. v

And a further object is to mount said belt relative to said stylus so that it serves as the means for normally holding the stylus in engagement with the recording surface, or at least a part of a means for this purpose.

The novel features that I consider characteristic of my invention are set forth with particularity in the appended claims. The invention, itself, however, both as to its organization and its methods of operation, together with additional objects and advantages thereof, will best be understood from the following description of specific embodiments when read in connection with the accompanying drawing in which, I

Fig. 1 is a side elevation, partly in section, of a recording apparatus including a recordin stylus mounted in accordance with a preferred embodi ment of the present invention, and

Fig. 2 is a top plan view of the recording apparatus shown in Fig. 1, and with the top of the housing removed to clearly show the manner of mounting and moving the stylus.

Like reference characters refer to corresponding parts throughout the drawing.

Briefly, according to the present invention the stylus or pencil is rotatably mounted in its support and means are provided for automatically rotating or oscillating the pencil continuously during a recording in order to maintain the same pointed, or to prevent it from becoming flat" on one side. In the preferred embodiment of the invention, the stylus oscillating mechanism includes a pulley carried by the stylus and normal}- ly engaging a stationary belt so that the movement of the stylus relative to the recording surface automatically causes an oscillation of the stylus relative to said recording surface.

Referring now to Fig. l, a recording apparatus according to the present invention may comprise a housing. l adapted to entirely, or partially, enclose the mechanism. Within the housing I0 is suitably located a recording surface supply and feeding mechanism, which I have chosen to show as a supply roll II for the recording surface 3, which in this instance is a long web of paper, a take-up roll l2, and a mechanism, indicated broadly at l4, for driving the take-up roll at a known rate. Between the supply and take-up rolls the recording surface |3 passes over a drum 15 which serves as a surface against which the recording stylus works as will b hereinafter set forth. It will be observed, that th drum I5 is so situated relative to the supply and take-up rolls that the recording surface is held flat and under tension while passing over the top thereof so that the stylus will make an accurate and sharp trace on the paper.

As is well known, the stylus is mounted in a support which is subsequently moved in response to variations in the conditions which it is desired to record. In the present instance, the stylus is shown as a pencil l6 of the mechanical type in which a separate lead I! can be placed and locked in an adjusted position by relative rotation of two parts of the pencil body. The pencil I6 is rotatably supported in a bracket l8 by having two forked arms I9 and thereon engaging shoulders on the pencil body, as clearly shown in Fig. 1. As clearly illustrated, the bracket is so constructed that it is adapted to support the pencil above the drum I5 with the lead I! engaging the recording surface at an angle. I

The pencil supporting bracket is carried at the free end of an arm 2| which is pivoted at 22 to a bearing 9 extending vertically downward from the top of the housing. Accordingly, the pencil is adapted to be moved substantially laterally of the direction of movement of the recording surface to make a record of variations in a condition that it is desired to record. The pencil supporting means is adapted to be oscillated by a mechanism including a driven disk 23 having an eccentrically mounted pin 24 in engagement with .an elongated slot 25 in the arm 2|. Inasmuch as the arm 2| is preferably made of thin gauge resilient material for reasons hereinafter fully set forth, a slotted bearing strip 26 of heavier gauge material is fastened to the arm 2| in alignment with the slot 25 therein to form a suitable bearing surface for the eccentric pin 24 which acts to drive the arm back and forth, I

The disk 23 is fixed to the upper end of a vertical shaft 21 which is journaled near its lower end in a bearing 28 carried by a supporting bracket 29 connected to the walls of the housing, and has fixed to its lower end a gear 30. This gear 30 is adapted to be rotated by a rack 3| reciprocally mounted in the housing on rollers 32 carried by the supporting bracket 29 in response to variations in the conditions which it is desired to record. Inasmuch as the rack 3| could be reciprocated by a suitable mechanism in response to changes in temperatures, pressure, or any other one of a number of conditions, as is well known, it has not been considered necessary to show any specific mechanism for moving the same in response to any one condition which might vary. From the description up to this point it will be apparent that any reciprocation of the rack 3| caused by changes .in a given condition, such as pressure, will cause an oscillation of the pencil supporting means and the pencil substantially laterally of the recording surface as it moves under the pencil, and that a trace on opposite sides of a reference line on the recording surface will be made to give a record of changes in a condition which one may be interested in.

Coming now to the present invention, it is desirable that a point be maintained on the lead in the pencil throughout a run so that a clear and distinct trace of uniform width and density will be obtained. To this end, I have rotatably mounted the pencil IS in its support and have fixed a pulley 34 to the body of the pencil as shown. This pulley is normally engaged by a belt 35 extending substantially laterally of the direction of movement of the recording surface and fixed at its oppoiste ends to posts mounted on a stationary part .of the apparatus. Accordingly, as the pencil is moved back and forth across the recording surface in response to variations in the condition which it is desired to measure, the pulley 34 will roll on the belt 35 and cause the pencil to be continuously oscillated in its support and relative to the recording surface so that a different portion of the lead I! will be used from time to time and the same will, therefore, be maintained pointed.

As clearly shown in Fig. 1, the points of fixation of the ends of the belt 35 are preferably located below the point of wrap of the belt with the pulley so that the tension in the belt will tend to hold the pencil in contact with the recording surface l3 on the drum l5 at all times. In order to increase the tension in the belt to insure its engagement with the pulley, and to obtain the desired pressure between the pencil, and recording surfaces, a spring 35' may be interposed between one end of the belt and its point of fixation, as clearly shown in Fig. 1. It may be desirable with a recording apparatus of the type set forth to be able to raise the stylus fromthe recording surface manually at the option of the observer, or periodically by an automatic means. By way of illustration as to how this can be done, I have shown a means for manually raising the stylus when desired. Referring to Fig. 1, the lever 36 is fulcrumed intermediate its ends on a stud 31 carried by a support 38 fixed to the walls of the housing l0. One end of this lever is located directly below the stylus moving arm 2| and is normally removed from engagement with this arm by a spring 39 connected thereto and to the support 38. A stub shaft 40 fixed to the other end of the lever 36 slidably extends through an opening 4| in the top of the housing and terminatesin a push button 42. By pushing downwardly on the push button 42 the lever 36 will be pivoted about its fulcrum and an upward pressure will be applied to the arm 2|; and due to the fact that the arm 2| is made of resilient stock, along with the fact that the point of upward pressure is substantially remote from the pivot point of the arm, the arm will 'be sufiiciently flexed to raise the pencil from the recording surface. The manner in which the belt is mounted relative to the pulley permits .the pencil to be raised without disrupting the moving mechainsm set forth, but could be used with any type of recording mechanism since it is only the movement of the stylus, not the mech anism for moving it, that is necessary to an operation of the present invention. Providing a stylus oscillating mechanism which makes use of the normal movement of the stylus as a motivating source provides an arrangement which requires a minimum number of parts and an arrangement which can be readily applied to any outstanding recording apparatus without difiiculty. Furthermore, the stylus oscillating mechanism is adapted to provide the entire, or at least a part of, the force normally holding the stylus in engagement with the recording surface, in addition to permitting the stylus to be raised from the recording surface without disrupting the driving connection for oscillating the stylus.

Although I have shown and described certain specific embodiments of my invention, I am fully aware that many modifications thereof are possible. My invention, therefore, is not to be limited to the precise details and constructions shown and described, but is intended to cover all modifications coming within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A recording apparatus comprising in combination supporting means for a record receiving surface, means for moving the same, a pointed stylus, means for rotatably supporting said stylus in an inclined relationship with said recording surface and normally holding it in contact therewith, whereby it is adapted to leave a trace on said record receiving surface as the result of relative movement between the two, means for moving said stylus supporting means and the stylus relative to said record receiving surface and substantially laterally of the direction of movement thereof in response to a variable condition which it is desired to record, and means for oscillating said stylus relative to its supporting means and the record receiving surface in response to its movement relative to said record receiving surface to maintain the stylus pointed, said last mentioned means including a pulley movable with said stylus and connected thereto to rotate the samewhen it is itself rotated, and a cord extending substantially laterally of the direction of movement of said record receiving surface and connected at its opposite ends to stationary parts of the apparatus, said cord adapted to frictionally engage said pulley at all times.

2. A recording apparatus according to claim 1 in which the ends of the cords are located in planes vertically displaced toward the record receiving surface from parallel planes including the points where the cord engages the pulley, whereby the cord due to the tension therein constitutes one of the means for normally holding the stylus in contact. with the record receiving surface.

3. A recording apparatus according to claim 1 in which the fixed ends of the cord are located below the point of wrap between the cord and pulley, whereby the cord due to the tension therein constitutes one of the means for normally holding the stylus in contact with the record receiving surface, and a spring interposed between one end of the cord and the fixed part of the apparatus to permit the stylus to be raised from the record receiving surface without disconnecting the cord from the pulley.

4. A recording apparatus comprising in combination supporting means for a record receiving surface, a pointed stylus, means for supporting said stylus in an inclined relationship with said surface and normally holding it in contact therewith, whereby it is adapted to leave a trace on said surface as the result of relative movement be- .tween the two, means for moving said stylus through its supporting means relative to said surface in response to a variable condition which it is desired to record, and frictional driving means for automatically and continuouslyoscillating said stylus relative to its supporting means and the record receiving surface in response to its movement relative to said surface to maintain the stylus pointed, said last-mentioned means including a driven member carried by the stylus and a flexible driving member frictionally engaging the same and fixed to a stationary part of said apparatus, and which driving member due to its flexibility aids in normally holding the stylus in contact with the record receiving surface.

5. A recording apparatus comprising in combination supporting means for a record receiving surface, a pointed stylus, means for supporting said stylus in an inclined relationship with said surface and normally holding it in contact therewith, whereby it is adapted to leave a trace on said surface as the result of relative movement between the two, means for moving said stylus through its supporting means relative to said surface in response to a variable condition which it is desired to record, and frictional driving means for automatically and continuously oscillating said stylus relative to its supporting means and the record receiving surface in response to its movement relative to said surface to maintain the stylus pointed, said last-mentioned means including a friction wheel fixed to said stylus, and a longitudinally resilient surface fixedly attached to said recording apparatus adapted to be frictionally contacted by said friction wheel at all times.

6. A recording apparatus comprising in combination a supporting means for a record receiving surface, a pointed stylus, a supporting means for holding said stylus in an inclined relationship with said surface and including a flexible member which normally holds said stylus in contact with said surface and permits the stylus to be lifted from said surface, means for reciprocating said stylus transversely of said surface and including a driving member operatively connected to said flexible stylus supporting member, the operative connection between said driving member and flexible member being one which permits the flexible member to be flexed to raise the stylus OTTO WITTEL. 

